1. Field of the Invention
The present invention relates to a method and apparatus for sweeping the bottom of a body of water around a central point such as, for example, a well head. More specifically, the invention relates to a method of locating and removing objects from the bottom of a body of water around a central point using a vessel and a cable or chain, with or without a net attached thereto, one end of the cable or chain being attached to a winch on the vessel, and the other end of the cable or chain being attached to a swivel assembly placed over a vertical pile located at the central point.
2. Related Art
U.S. Pat. No. 4,802,292 shows an apparatus for mining materials from the bottom of a body of water. The apparatus includes an endless rope, a driving mechanism and a large number of buckets, all attached to a vessel. The vessel is steered ahead as the driving mechanism continuously feeds out the endless rope with attached buckets. This apparatus does not provide a means for removing all objects on the bottom of a body of water within an area circumscribed by a circle of predetermined diameter.
U.S. Pat. No. 4,055,006 shows an apparatus for hoisting ores from the bottom of a body of water. A number of nets are provided on a flexible, endless member hanging from an ore-collecting vessel, and a separate ore collecting and filling mechanism is towed by a winch connected to a power and towing vessel floating ahead of the ore-collecting vessel. This apparatus requires the use of two vessels, and does not provide a means for removing all objects on the bottom of a body of water within an area circumscribed by a circle of predetermined diameter.